About some days ago the internet stopped working.
I noticed that if I manually changed the DNS to OpenDNS's IPs, or Google Public DNS's IPs, on the Network Settings, the internet worked again.
If the router is left alone to solve the DNS by itself, without manually setting a Public DNS, the internet doesn't work.
This problem seemed to start some days ago when to router updated itself.
I've set the Google Public DNS's directly on the router, but when I remove these DNS's from the local configuration on the computer, leaving it blank, the internet still doesn't navigate, even after cleaning the cache (
It turns out that the router was solving DNS correctly, the problem was on the switcher device which was messing up with the DNSs when redistributing them.
Reseting the switcher to its factory default settings solved the problem.
Anyway, we now use OpenDNS's public DNS just in case something similar happens again.